Modular batteries are made of battery modules. Battery modules allow easy replacement of a defective module. The battery modules can be coupled together in series or parallel or combinations of series and parallel. Smart battery modules have in-module electronic circuits that monitor conditions or aspects of the batteries, such as temperature, cell voltage, current, etc. However, an interconnect defect can occur between battery modules, such as a corroded or damaged connector or wire, which can be difficult to recognize or diagnose. External diagnostic equipment can be applied after a failure, for example by a technician at a repair facility, which is costly and inefficient. It would be desirable to have improvements in onboard or in-system monitoring capability for the battery modules in order to more efficiently test the module prior to assembly into a system.
It is within this context that the embodiments arise.